Surgical cutting guides are used in orthopaedic surgery to prepare bone surfaces to receive an implant. Depending on the nature of the surgery, the cutting guides may have various configurations. In orthopaedic knee surgery, some of the cuts which are required to be made on the femur include chamfer cuts which are made on the anterior and posterior side of the lower extremity of the femur. The two chamfer cuts are made along planes, which intersect at a position away from the lower extremity of the femur.
It is known to provide a combined cutting guide that defines planes for both the chamfer cuts. One such guide is fixed in place on the bone and can guide a cutting implement such as a saw to cut in the two planes required for the two chamfer cuts. For example in the S-ROM (RTM) knee system commercially available from DePuy International Limited, UK, a cutting block is provided which is machined from a solid piece of metal. Slots are machined through the solid block of metal to define the two planes for the chamfer cuts. A disadvantage of such a solid machined block is that it is expensive to produce and therefore not suitable for use as a single use instrument.
It would be desirable to provide a cutting guide with sufficiently low manufacturing cost that it can be provided as a single use instrument, simplifying inventory and removing the requirement to sterilise/decontaminate the instrument between uses.